Variable speed governing mechanism with modifier



M. FRENKEL Oct. 20, 1953 VARIABLE SPEED GOVERNING MECHANISM WITHMODIFIER Filed March 30., 1950 a Sheets-Sheet 1 F INVENTOR- Oct. 20,I953 FRENKEL 2,656,173

VARIABLE SPEED GOVERNING MECHANISMWITH MODIFIER Filed March 30, 1950 .8Sheets-Sheet 2 INVENTOR i- FIGr MEFUMUL Oct. '20, 1953 M. FRENKEL2,656,173

VARIABLE SPEED GOVERNING MECHANISM WITH MODIFIER Filed March so, 1950 sSheets-Sheet 5 Oct. 20, 1953 FR'EjNKEL 2,656,173

VARIABLE SPEED GOVERNING MECHANISM WITH MODIFIER Filed March 30, 1950 8Sheets-Sheet 4 INVENTOR Oct. 20; 1953 v M. FRENKEL 4 2,655,173

VARIABLE SPEED GOVERNING MECHANISM WITH MODIFIER v Filed March so, 1950s Sheets-Sheet 5 1953 M. FRENKEL 56,173

VARIABLE SPEED GOVERNING MECHANISM WITH MODIFIER I Filed March so, 1950s Sheets-Shet 7 INVEN TOR OctQZO, 1953 ,M. FR ENKEL 7 VARIABLESPEEDGOVERNING MECHANISM WITH MODIFIER Filed March 50, 1950 8 Sheets-Sheet -8I INVENTOR Patented Oct. 20, 1953 "vzimanmgzsrnnn *GOVE-RQNING MEGHANISMfJWTHMOmFIEB h.

1 :Mexerrfinenkel, Lcn lgnghpgland *The :present application is;acontinuation in- =part app1ication foi the application Serial -No. 11:;-841',- mes. n ust 2-2-, 1c49,-mew abandoned;

Thisr-inventio1rrei-ates to variable speedgoverningmeehanism comprisingaspeed responsive "device ta -g. a centriiugal mehanism)sand anacijustabie iiient balancing mechanismytherefor; a vhere sa ci halancingmechanisrn inclufd'es a levertransmission arrangement between aslpx 'ingmeans and a sieeve ofisaid-speed responsive-device, which is=adaptet1=tohave motion respon'sive to changes -*of- }speed =of rotation. mhe'g'enera1 -'-*thecry underlying this invention is given inithepaper'entitied- Formu-lation ci stabiiity equations and derivation df newconstructions, with-mommlex systems of tiesign-fiormiilaefforvariablespeed control mechanismsg puhiished ingthewro- -ee eEiings Gfth-e Institution of Mechanical Enginee'rs, tendon -1 953. v

"This invention; also relates to variable speed governi-ngmeehanismscomprising nreans for ade jfisting the frictional resistances.

Phe performance of --a gv-ar" 'lp'ie speed governor 5 fisfleterniirredby th-ree gmain' influences; vim-the fiectofthe?speedresporrsive device(-such -as a entrifugaLm ech-an-ism) r the g'e'fiectoflthe resilient -ba1anc'ing mechanism ssuch-fas a -=spring lever a ae i m cha is is ndhe ni assette-s ns g v ier H 1.'e: th e1resist- -ance*of the control-crganof he paratus to be governed, together with aii otherfnicticnalresistances.

The fundamental differences between these in-' "denoted crum B of the 1thereon of the balancingitspring, with reference to a system of co-ortiinates having its origin Lt ancels iromitsvmid v j later) lifficiiefforejt is re can be positive or ne mgl 25 resistance may, at-ithe saplessiceikp flpi ii rum cas Yams 9 t e.

am s i fia f r e ev tance z from thefniixi-position thereb where at oneand. the same sleeve-position at a crtain speed-setting, correspondingto certain values of aanamhe momen c t ataleatma ssh lei can have onlyone value, vizLSk, z

0 In contrast to this, the moment of the speed responsive device at'thefulcrum of the lever, --which is a function :of rthe sspmgile-speeqirand rwili-zhence'beaienoted by eeway-nat ona-anci the samesleeve-position have idifierent v M s of zthes fimfi f tioi the the onandlcoii'trp different values, including 'z'ro.

In the static state, at which the moment of the frictionandcontrol-orgamresistanceismero, e. these are not in action, the moment Lof 30 the centrifugal mechanism must equal ,the mo- .me t s. .ha baancing mech nism the sleeve-pd ioiijfland speed-"set f'g fin question,imwheneft a vsi epr oment t siestores a {l ce ainfvai uetofither-spindlesped. wh nh w't spin l -speed ch e esz tm t r; certain QvaIue at flthes'arne sieeve-po siticn the qimlleof,thefcentriiugal mechanism "tbeingmnaion of w)" enga s.f me-magm z) remains the same at the samesieeve-positionat the same speed-settin ,and the resulting difference inthe moments calls into action the moment I r of' the ccntrol organ orthe :enginerheing {governed, andof frictional resistance,:to :maintain45 static equilibrium. With progressivecchangedn the spindle-speed, thedifference ,hetvveen the moments of the centrifugal mechanism and theabalancing,tmechanism grows until a st to is h a; reached in which(motion of the sleeve about to: start, ige. henQthe difference "the'moments La: and. Se equals the momenta i w lnes z QaQQ Q T-Q1 F f? sets thefriction. I

Thus, in the state when the friction-antican- 515 twi organ resistancesare notinaction and there and for the mid-position of the sleeve, wherewill be is hence game is equilibrium at a certain sleeve-position andspeed-setting between only the balancing moment S(x,z) and a certainvalue of the moment L of the centrifugal mechanism, to which correspondsa certain value of the spindle-speed to, this value of the spindle-speedmust, just like moment S(x,z) be dependent on the variables x and z, andone can therefore denote it by w and the corresponding value of themoment of the centrifugal mechanism by Ltc z) where corresponding tos(x,z), the suffix .r denotes the dimension characterising theadjustment of the spring-lever balancing mechanism in the midposition ofthe sleeve, and the suffix z the ordinate of the sleeve-position in thesystem of coordinates having its origin at the mid-position of thesleeve.

This state is the beginning of static equispeed-setting, thespindle-speed corresponding to it being w and its equation ofequilibrium generally W(Z.I) (ZII) where w is the spindle-speedcorresponding to the mid-position in that speed-setting, in short, thespeed-setting.

However, for the spindle-speed changing from a value m nism will atfirst not go to change the sleeveposition 2, but'will first bring intoaction the moment of the control-organ and friction resistance, so thataccordingly, this change of moment of the centrifugal mechanism willhave nothing to do with changes in ac and a, but corresponding to achange of spindle-speed A bringing the moment toavalue where F is themoment of the friction and conv trol organ resistance called intoaction. N

If one denotes by Ana; the change in spindle speed from e which bringsabout a change from the beginning" of static equilibrium to a state whenmotion (of the sleeve, lever, etc.')- is about to start, i. e. when thechange in moment the friction and control-organ resistance, according tothe state brought about by this change is the end of static equilibriumin relation to a: and z,

also denoted by equilibrium at the end of a steady state.

The equation of the end of static equilibrium (w =.1)d:AFw)= QIiI z vNow, in order to determine the constructions for beginning of staticequilibrium, the change of moment of the centrifugal mechaof resilientbalancing mechanisms (e. g. springlever balancing mechanisms) inrelation to the requirements for required performance of the governor atdifferent speed-settings, one has to derive equations in which only theinfluence of the centrifugal mechanism and the influence of theresilient balancing mechanism are represented, while the influence ofthe control-organ resistance and of friction do not occur, and this hasbeen done in the above-mentioned paper published by the Institution ofMechanical Engineers, London, 1953.

(1) It is the object of this invention to provide constructions ofvariable speed governing mechanisms, which can be adjusted to anyspeed-setting over a wide range with only one actuating motion andwithout obstructing governing, and which should govern stably for eachspeedsetting of this range. This requires that, at any onespeed-setting, the governor should provide for any value of the shaftspeed its corresponding position of the control-sleeve, at which thegovernor is at the beginning of static equilibrium, and vice versa, thatfor any one speedsetting, to each position of the control-sleeve shouldcorrespond its value of the shaft speed, at which the governor is at thebeginning of static equilibrium, Where the extreme values of suchspindle-speeds correspond to the extreme positions of saidcontrol-sleeve, and thus to the extreme adjustments of the control-organof the engine being governed, and where, as defined, the speed-settingdenotes the shaft speed corresponding to the mid-position of thecontrolsleeve, at which the governor is at the beginning of staticequilibrium.

(2) The governor should be sensitive at each speed-setting, for example,the governor should, for each sleeve position at any one speed-setting,begin governing action for the smallest change of the shaft speed fromthe value for the beginning of static equilibrium, limited only by thecondition that the overnor should not be sensitive to the unavoidablevariations of shaft speed occurring in a state of constant mean shaftspeed. Expressed mathematically, this means that twice the difference inshaft-speed AFw from the beginning to the end of static equilibrium atany sleeve-position, expressed as fraction of the speed-setting anddenoted by the degree of insensitivity of governing, should be a minimumfor each speedsetting, limited by the condition that it should not besmaller than t, the degree of speed-fluctuation of the rotating masses,which is twice the greatest deviation n w from the mean shaft speedwhich occurs at constant mean shaft speed, expressed as fraction of thespeed-setting Accordingly this object is to make e zrfx for eachspeed-setting, in order to bring about governing at a predeterminedsmallest deviation from the mean shaft speed, but to prevent thegovernor being sensitive to the variations of shaft speed at constantmean shaft speed. For the degree of speed-fluctuation 5X of the rotatingmasses varying over the range of speed-settings, as e. g. inreciprocating engines, it is thus the object of the invention to provideconstructions, in which, with the one adjusting motion for change ofspeedthe nth order, 1. e. which bring the construction into accordancewith the above difierential equations of the first to the nth order; foreach speedsetting of the range with only one adjusting motion for changeof speed-setting.

It must be stated generally that as a minimum requirement a spring-leverbalancing mechanism has to satisfy at least the stability-differentialequations of the first order (25) and of the second order (32), becauseit will be understood from a series expression for the moment s(x,z) atany sleeve-position in terms of the moment Se m at the mid-position andthe derivatives thereof, that a governor merely satisfying thestabilityequation of the first order can only be stable for a very smallsleeve-travel about the mid-position of the sleeve, and that a governormust at least also satisfy the stability-equation of the second order inorder to be stable over a normal sleeve travel, and that it shouldpreferably satisfy higher orders of stability-equations as well.

movable along the lever for a change of speedsetting, but fixed for thesame speed-setting, and which spring is suspended at A to an anchoragesupported so as to be immovable also for change of speed-setting. Forgoverning action at the same speed-setting, e. g. rocking of the leverabout its fulcrum B with motion of sleeve D, the spring-means, suspendedat points and A, rocks about these points. With distance CA representingthe total length of the spring between its points of suspension, thedeflection ZX of the spring beyond its unstrained length U0,

I which deflection determines the force exerted by the spring, isrepresented by length CA, leaving the length AA to represent theunstrained length U0 of the spring.

With suspension as method of engagement between the spring and thelever, the moment of the balancing mechanism at its fulcrum wheredistance 80:30, and with k the rate of the spring, Zx its deflection andthe angle between the centre-line of the spring and the lever in itsmid-position.

The construction is characterised in that, for a change ofspeed-setting, the point of engagement C of the spring with the lever,which is immovable for governing at the same adjustment, is moved alongthe lever, rotating the spring about its point of anchorage A, whichremains fixed, and altering its total length A C. This motion thusadjusts: Firstly, the distance BC=$ between fulcrum B of the lever andthe point of action C thereon of the spring, secondly, the angle betweenthe centre-line of the spring and the lever in the mid-position, andthirdly, the deflection IX of the spring beyond its unstrained lengthU0, this adjustment of the deflection being determined by the motion ofpoint 0 along the straight lever and the motion of point A, whichrepresents the end of deflection Zx set 01! from C, in the arc of acircle with radius AA=U0 about the fixed support-point A, which circlerepresents the locus of points A for all adjustments.

For minimum stability, one has for each speedsetting the three equationsgiven by the equilibrium Equation 2, the stability-equation of the firstorder (25) and the stability-condition of the second order (32); Thesethree equations must be satisfied at each speed-setting, and since themoment Lm(x,0) of the centrifugal mechanism and its derivatives arefunctions of the speed-setting ti the equations will require for eachspeedsetting difierent values of x, lx and :11, the dimensionsdetermining 'S(x,o), which the construction should provide.

Whereas, however, the construction provides a development of thedeflection Zx with change of speed-setting, which is given by the motionof end-point C of the spring along the straight lever and the motion ofpoint A, denoting the end of the deflection set ofi from C, in the arcof a circle of radius U about fixed point A, the three equations would,in general, require a development of IX which, for the same motion ofpoint C along the lever, would make the point A move along some curve tosuit the equations, and not a circle with radius U about A".

Accordingly (as also proved exactly after the detailed description ofthe invention), such a spring-lever balancing mechanism cannot providethe minimum necessary order of stability over a range of speed-settings,due to the development of the deflection Zx being geometricallypredetermined. To provide a displacement of point A along a requiredcurve instead of along a circle about A one would have to adjustdistance AA=U0, the unstrained length of the spring, which, however,would require a second adjustment motion in this construction, which isagainst the object, and also has other faults, as shown later, whichmake this inapplicable. Therefore, in order to vary the deflection lx inaccordance with the stability-equations, while keeping distance AA=Uu,the unstrained length of the spring, unchanged during change ofspeedsetting, one has to be able to displace the point of engagement Aof the spring anchorage with its support, which is immovable duringgoverning at the same speed-setting, along a required path. This variesfor a change of speed-setting also the distance BA and angle 5 (see Fig.14), which determine the position of engagement point A, relative tofulcrum B and the lever, together with the other adjustments of thespring-lever balancing mechanism, and all this has to be done with oneactuating motion.

More generally, as will be shown hereafter, in order to provide theminimum order of stability, constructions have to be provided which,while displacing the point of engagement A of the spring anchorage withits support in order to vary the spring-deflection 2;; in accordancewith the stability-equations, also vary, with the same adjusting motion,at least another three of the dimensions of the spring-lever balancingmechanism, viz: m, A B, ,8, 3/, As, in accordance with thestability-equations, where A is the half sleeve-travel of the speedresponsive device. Furthermore, a construction such as thatdiagrammatically represented in Fig. 14 requires its adjustment means tobe connected to the lever DBC in order to be able to eifect displacementof the engagement-point C of the spring along the, lever during, changeof, speed-setting, e. g. the block from: which, the,springissuspended,may, be,

moved along the lever by means of, a, screw mounted thereon and actuatedthrough bevelgearing mounted, on fulcrurmB.

The present invention provides for adjustment means fcrthe spring leverbalancing mechanism,.

which isjentirely out of, contactt with the, lever,,

thus avoiding any frictional orother resistances,

to rocking of the lever-due to such. adjustment means either duringgoverning 'action'at. the.

same speed-setting, or more" particularly. during change of"speed-setting, which would obstruct the operation of the governor.

To achieve these objectsxthe present invention provides:

A variable speedgoverning mechanism which comprises a fixture; agovernor shaft rotatably mounted onsaid fixture, a,speed responsivedevice having a sleeve-member for performing motion. responsive tochanges of speed of rotation of said governor shaft, means fortransmitting motioirof-s'a'ld sleeve-member to a control-organ I of anapparatus tobe governed, andan adjustab'lespring-lever balancingmechanismxfon said speedresponsive device; which comprisesa levertransmission arrangement; a 'spring means,- an

anchoragefor said-spring--means; a: support for said anchorage in" allpositions of said anchorage,

a fir'st connecticn means engaging bothanother part of saidspring-meansand said lever trans mission arrangement,- a support forsaid-fulcrum, a second connection means engaging both said levertransmission'arrangement and said sleevemember of said: speedresponsivedevice, and a" speed-setting adjustment means comprising a first meansfor displacing relative to said fixture" at least one of threecomponentsrespectively-- re cited-fas said first connection means,- said-ful crum and said secondc'onnection meansra second means: fordisplacing-said anchorage of said spring means: relativeto 'saida'supporv'ofvsaidi anchorage, relative to said fixture and relative:

to said first connectionvmeans with;a change in the distance betweensaidanchorage andfsaidtfirst' connection means; said anchorage beingimmov able relativeto saidrifixture with said: displace? ment means inthe same position; and one actuating means for said first and saidsecond displacement means, the said actuating means being out of contactwith said' lever transmission arrangement; the said speed-settingadjustment taneously with only one actuating means and;

corresponding to one; another.

In otherwords; the invention provides for a springlevermechanism withmeans for-efiecting,

durin change of. pe dttin a c n transmissionratio of; the, lever, (by'one ofsev eral methodsz 'e. g. displacement oithe engagement' point ofthezfirst engagement" means from the spring means with thelevendisplacement of the fulcrum, or displacement of the engagementpoint of the second engagement means from the sleeve-member with thelever, or any combination of such displacements) and simultaneously withthis, due to the same adjusting motion, a change ofthe deflection oi thespring means at least for the mid-position of the lever throughdisplacement of said spring-anchorage, which is immovable relative.v to!the fixture. during govern:- ing at.,the. same speeds-setting, and;relative.- to). it's supporth relative, .to saidpfixture, and, relative"to said, first-connection means.

Also according to the present invention, a vari: able speed governingmechanism which com-- prises a fixture,- a governor shaft rotatablymountedeon: said- "fixture, a speed responsive de.- vice having a:sleeve-memben for performing mm; tion responsivesto; change of, speed:of rotation. of said governor shaft, and means for transmitting motionof said sleeve-member to a control-oramof an apparatusto, be' overned,has an adjustable spring-lever balancing mechanism which comprises: alever transmission arrangement, at;

spring means, an anchorage for said spring means, a support for.saidanchorage in all positions of said anchorage, a first connectionmeans engaging; both: anothen'part offsaid spring meansi and; said levertransmission 'anrangementia ful. crum' fon saidz lever transmission,arrangement: 1' support: for: said: "fulcrum; a I second: 'connectiorm':means engaging; both said; leverrtransmissi'om rangement and said sleevemember of," said speed a responsive; device;. a, means; for limiting:the; travelle of: said: sleeve member of saidi speed! .responsiveiidevice,-.: said; limiting: means; comprising an strips). and,speedesettin-g: adjustment meansfcomprisz-a ing a: first meansifor.displacing; relative to: saidm fixture r at; least one: or? fourcomponents: 'respec' tively: recited as said; first :connectionrmeans;said fulcrum,, said' second connection means; and said limiting: meansfon=the-.-:-.trave1% of saimisleeve-o i member of said speedresponsivedevicegtasecond-s means for displacing. ,saidw. anchorages ofssaid spring-means relative to said support ior-saidamchorage,relative-to, saidffixture and relativea tow said first connectionwmeans:with; a; change his. the distance-b.etween-,the-.saidianchoragee and thesaid first connection means, the saidianchoragew being immovablerelative to .said fixture with said; speed-setting adjustment:- meansbeing out of action; and one actuating means for said first and saidsecond displacement means-, thei:saidi? actuating: means beingaout; of:contact: with said'v; lever: transmission arrangement; that saidispeed- 1 setting adjustment means refiectingythec'saidz-dissplacements.i'ofr thei said'.. components; to: involves'achanger-in the deflectionIOfISaIidILSpIEiDQEmEaHSC an least' for the midepositionzofrsaidsleeve-member; and the: said: displacements of: thersaid ,com ponentsbeing. mutuallyi: interdependent; beings carried.out/simultaneously withonly one actuating means, andrcorresponding to one another.

In otherwords, such an adjustable spring lever balancing- I mechanismmay comprise means for effecting, at'changes ofispeed-Setting at leastin the mid-position- 'of said lever over-=' at least apart of the rangeof-* speed-settings; guidance-of the point of engagement A betweensaidspring anchorage-and said supportgwhich is-immovab'l'e relative tosaid fixture during governing-atthe-- same speed-setting, along avpathrelative to a system of -co-ordinates having; its origin fixed tosaidiulcrum B of said lever, and one axis along the, mid-position ofsaid lever; and for, effecting; said guidance of said; point ofjengagement; A? during change of ,speedesetting. with aichange of I the,deflection. Zaof, said, spring means; together. a with changesv of atleast another three, of, thee aforedefined dimensions of. the,componentscofh the springrlever balancing jmechanisnnnac; M3,; ,6, Ad,with ,only, one,actuatingmotionifor. said adjustment. means, Said, path.of, point, A relative to saidlsystem, oi,cogordinateshavingitsorirl wgin at the fulcrum B of said lever and one axis I along the mid-positionof said lever, is determined by the dimensions x, and Ux for eachspeed-setting, in accordance with the equilibriumequation E T,( r.o)wc.o

where n is any positive integer including unity, U==Uo: is the strainedlength of the spring means between the point of engagement A of theanchorage with its support and the point of engagement C of its firstconnection means with said lever in its mid-position, where Limo) andSew are the moments respectively exerted at the fulcrum B of said leverby the speed responsive device and by the spring lever balancingmechanism for static equilibrium between these two moments only, i. e.for the beginning of static equilibrium, in the mid-position of thesleeve, as defined before, and where z is the distance of said sleevefrom the mid-position of said sleeve, measured positively in thedirection of w increasing, as hereinbefore defined.

Adjustable spring lever balancing mechanisms in accordance with thisinvention embody one of the following two methods of engagement of thebalancing spring means with the lever:

(1) The method of engagement in accordance withthe relation whichrequires that the point of engagement C of the first connection meansfrom the spring means is movable during governing at the same Iiispeed-setting only in the direction of the line of action of thespring-means, which is maintained the same during governing at the samespeedsetting, so that said first connection means has to be guided to becapable only cf motion along as y zf *[LMM said line of action of saidspring, which is held stationary during governing at the samespeedsetting, and engages the lever movably therealong (e. g. by meansof a roller) during such governing,

(2) The second method of engagement in accordance with the relation (1)For the first method of engagement, of the I spring means and lever, theequilibrium equation becomes 1 70.1131, L =0 for any speed responsivedevice being used in the governor, Lw(X,U) being known therefore interms of its properties and of ti (a) Generally, for any speedresponsive device, the stability-equation of the first order becomeswith such a spring-lever balancing mechanism sin 1 dLe =,9 m dz ;,3 2cot (128) and the stability-equation of the second order 1 d L 1 g y-Sim 6v cos +4 cos 4 +2] and so on for higher orders of stability-equalstions. From these equations is determined the path, along which theadjustment means for the spring lever balancing mechanism displaces,during a change of speed-setting, the point of engagement A between thespring anchorage and its support, said path being traced in the systemof co-ordinates having its origin fixed to the fulcrum B of said leverand its X-axis along the mid-position of said lever, and said path beingdetermined by the dimensions at, and Ux, which are obtained for eachspeed-setting from the above equilibrium and stability equations up theorder required, where Ur UOilm for a tension or compression springrespectively. In Equations 128, 125, and so on, the derivatives ofLw(X,O) will be known for any speed responsive device, in terms of w andof the properties of the device, the expressions containing 5m(X,0) thedegree of irregularity of the governor for the speedsettings.

(1)) Still for any speed-responsive device, expressing the derivativesof Lteem in terms of the degree of irregularity mo e) and of the halfsleeve-travel Aa (for the condition that P3 21 Dz the same for allsleeve-positions), the stabilityequation of the first order becomes andconstant for all values of 2, as is given by a ball and. conical cuptype centrifugal mechanism, for which half apex angle of the cup theratio zgeaa wae the stability-equation of the second order;

the stability-equation ofzthe th-ird order:

Ag; sin? M? 154 witmi-ts: origin at .thesfulelium -B? ot; thez.laver;-,azndz itsxeaxi'szalong the midhpefitionk 0.1 he :lev

(b); Expressing: thx derivatives: of I Ema) terms: of; thevde neea ofirregularity-6mm); and

the. half sleeve-travel; (for :the hconditiomthat:

is chesam for. all;s1eeve;-pnsitions-*) -5 thegstabilifig quati n ofthe-first rdenb eom s b1413 dR x cot- 5 cos 5 H 2 1""5RT ("1 3%thedimensions of, the speed responsiy'e; device-be mgasdeflned-flnderflase (1 .b, andthe ,stabilitk; equatipns of.- higherorders, can beeexpressed 'ing thisform.-

(0), Taking: the same: example of: an:sp ed. im;-- sponsive deviceasunder Case-(lie, say aubill; and. 001110311, cup tyge; centrifugalmechanism asj, them-defin d, t e: equ brium. quation; becbmes E cot-$00353; Ui'l};

and. soon for, higher:- oliders,of,sta;bi1ity-equa ti-ons, giving.;-thesystemsofeeqyatians for deizeg mining. the path. of, engagemenfipointwA9. 11 131 tive to the-systemof qoardinatesvhaving itsfpm; gin, fixed.tom the. fulcmmwEflof 'thejlevergfiand; its X-axis .along" the-mid-p0s'iti0n Qf the 1e3leiias-= explained for Case-1 oflethefotherpengagement; means; e

Embodiments ofthevpresentwinventibmwitli,re? gard 7 tospeedwsettingfladj ustm'ent -means [efiiit ing, with one actuatingInOliiOn.adjeustniiehl' of: the dimensions, J-of, the springrlevei gbalanih mechanism. in--vaccor dance with. the; stability equationjggiyehbfp're can, he, of. thflfliOflOWifi: nd 01' can: ecombinations thereof,as idea cribei, by,- way oi} example and; in some detail. with,reference to". the accompanying. draw-m3,

' hereafter:

(A), The spring-lever, balancin mec aIi Siii camprisesn means forguiding aid. fir t; qqnnecfi-e ticmz me ns en a in said spring with.lever? bq be capableof;mbt mhnlynalong, estmiglitiline. fixed-."11e1ativeto'saidlarichara which is 11mmIiv;-; ablexdurin fi govern ngat, he. same. sn ed se ting '(-sa;id;strjaight; lir'ielbeing hereafterreierxed' ma thenne' f,action;oilthegspfin means) ame-Z sea'icl firs t"connectiomenga es; he lever; In! vainly,v

therealbn j "g by, means, of? a, roller, thus-iem-gi' bqdyin iheinethqd;oienga' ment' in conf rmity? wl litherelation. e

as stated befbre; The jad pstrhentmeafis' 03 change,of'spemsetting'icomigrises a fiist guide? surface mbuntedonth fixture,and being ati all surface, varying the deflection Z): of the spring atleast for the same mid-position of the lever, as well as the dimensionsBA and angle ,9, giving the position of point A in the system ofco-ordinates with its origin at fulcrum B, and its X- axis along themid-position of the lever. Thus as, Zx, BA and ,8 are variable inaccordance with the stability-equations. 'For example, as shown in Fig.1, both the anchorage for the spring means and the guide-means for thefirst connection means may be mounted in a guidecarrier, which isdisplaced parallel to itself for a change of speed-setting.

(B) Irrespective of the method of engagement between the spring-meansand the lever, the adjustment means for a change of speed-settingcomprises a carrier for the support of the fulcrum of the lever, asecondary guide-surface for adjustably mounting the anchorage of thespring-means on said fixture, which secondary guide-service extendsparallel to the centre-line of the spring means, a transmission meansbetween said carrier for said fulcrum (B) and said anchorage or saidspring means, and means for adjusting for a change of speed-setting, theposi tion of said carrier relative to said fixture (see Figs. 6, '7, 8and 10), which adjustment involves a displacement relative to saidfixture of the fulcrum of said lever, thereby adjusting distance 30:0:(and distance BD=y, though in a goometrically predetermined way for thelength SD of the lever constant) and, through said transmission means, adisplacement along said sec ondary guide-surface of said anchorage forthe spring, which adjusts the deflection Zx of the spring at least forthe same mid-position of the lever, as well as dimensions BA and ,8,giving the position of engagement point A relative to the system ofco-ordinates having its origin fixed to the fulcrum of the lever and itsX-axis along the mid-position of the lever. The dimensions lx, :r, BAand 3 are thus adjustable in accordance with the stability-equations byhaving suitably shaped slots in the transmission means, adjustmentproceeding with one adjustment motion only.

(C) Irrespective of the method of engagement between the spring-meansand the lever, the adjustment means for a change of speed-settingcomprises: said second connection means between said lever and saidsleeve-member of the speed-responsive device with provision (such as aroller) for engaging said lever movably therealong and provision forengaging said sleevemember movably relative thereto in the directionparallel to the mid-position of the lever, a carrier for said secondconnection means, a guidemeans in said carrier for permitting motion ofsaid second connection means, during governing, only parallel to thedirection of motion of said sleeve-member; a secondary guide-surfaceinsaid fixture for adjustably mounting said anchorage for saidspring-means, said secondary guide-surface extending parallel to theline of action of said spring-means, transmission means between saidcarrier and said anchorage for said spring means (e. g. a guide-slot inan extension from the carrier, or a secondary lever, as shown), andmeans for displacing, at a change of speedsetting, said carrier relativeto said fixture. Such adjustment involves a displacement along saidlever of said-second connection means, thereby adjusting the distanceBD=y, and a displacement along the line of action of said springmeans ofthe support therefor, which involves adjustment of the deflection 1;; atleast for the same mid-position of the lever, as well as adjustment ofdimensions BA and 8. The dimensions Zx, y, BA and 18 are thusadjustable, with one adjustment motion for a change of speedsetting, inaccordance with the stability-aquations, which determine the shape ofthe slots in the transmission means (e. g. in the extension from thecarrier, or in the secondary lever, as shown).

(D) As seen with reference to the example of Fig. 12, with the firstconnection means between the spring-means and the lever having movableengagement the lever (e. g. through a roller) and being guided so as tobe capable of motion' only along a straight line fixed during governingat the same speed-setting relative to a then immovable anchorage inconformity with method of engagement according to da; E x cot thespring-means is mountedin a guide-carrier, which mounts said guide-meansfor the first engagement means at one end, and has a secondaryguide-surface for adjustably mounting the anchorage for saidspring-means, said secondary guide-surface extending along the line ofaction of the spring-means. The adjustment means for a change ofspeed-setting comprises: a first guidesurface mounted in said fixture,for engaging said anchorage of said spring-means, a shaft rotatablymounting said guide-carrier for said springmeans in said fixture, andmeans for rotationally adjusting, for a change of speed-setting, theposition of said guide-carrier relative to said fixture. This adjustmentinvolves adjustment of the angle 4) between the line of action of thespring means and lever in its mid-position, displacement of engagementpoint C of the first connection of the spring means with the lever alongthe lever, and thus adjustment of the distance BC=0:, and a displacementof the anchorage of said spring means along its first guide-surface inthe fixture, which involves displacement of said anchorage along theline of action of the spring means, and thus adjustment of deflection IXof the spring-means, at least for the same midposition of the lever, aswell as adjustment of the dimensions BA and angle ,3, defining theposition of point A relative to the system of coordinates having itsorigin at, fulcrum B and its X-axis along the mid-position of the lever.Dimensions 0:, Zx, BA and n are here adjusted with one adjusting motion,but since point G of rotation for the guide-carrier is fixed in the fixture, the adjustment of one of said dimensions is geometricallypredetermined, leaving four of these dimensions (including Zx)adjustable in accordance with the stability-equations, which supply theshape of the first-guide-surface for the anchorage of the spring-means.

(E) In a; construction as defined in the foregoing paragraph (D), theshaft mounting the guide-carrier is also mounted in a carriage, which ismovable relative to said fixture during change of speed-setting, apartfrom the guide carrier being rotated relative to said fixture, all withone adjusting motion for a change of speed-setting. Then the dimensions1x, 3:, BA, 5 are adjustable in accordance with the stability-equations,which supply the shape of the first guide-surface and the motion ofpoint G required.

The order of stability provided by any of the constructions generallydescribed in the foregoing a sence can'bein'creased to:any,requiredorder, through remains constant for all speed-settings, x beingdeterminable as function of the properties: of the engine to be governedfor each speed-setting, and

by determining the constant dimensions on the right hand sides of thestability-equations of the second, third, fourth and so onstability-equations in accordance with these equations. Without makingany further dimensions variable with speed-setting adjustment, theseconstructions provide as high an order of stability as the order ofstability-equationsfrom which variable and invariable dimensions havebeen calculated, with the-minimum number of dimensions adjustable. Suchprovision compriseaas will be understood with'reference to the exampleof Fig. 5, a transmission member movably mounted in said fixture and.connecting to the control-organ of the apparatus to be governed; a thirdconnection means for engaging said lever movably therealo'ng and forengaging said transmission member movably relative thereto in thedirection parallel to the mid-position of said lever, a carrier for saidthird connection means, a guide-means in said carrier for permittingmotion of said third connection means only along'a straight'line fixedrelative to said carrier (hereafter referred to as centreline of saidcarrier) and inclined to the'midposition of said lever, stops forlimiting the motion of saidthir'd connection means relative to saidcarrier therefor, and means for displacing, with the same adjustmentmotion as actuates the adjustment 'means for the spring-leverbalancingmechanism for a change of speed-setting,

said carrier for said third connection relative to said fixture, withthe centre-line of'said carrier parallel to itself. Thereby the distanceof the engagement point of the third connection means with the leverfrom the fulcrum of the leveris adjusted, and thereby the magnitude ofthe half-' travel Aa of the sleeve of the speed responsive device whichcorresponds to the sain'e travel between its stops of the said thirdconnection means to said control-organ of the apparatus to be gov erned;are adjusted in accordance "with the sta-- bility equations;

' Constructions of higher orders of stability may also be provided bycombinations of the embodimerits generally described above;

The invention will now be described by way of example and insome'detail,reference beinghad to'theaccompanying drawings, in which:

Fig. 1 shows a sectional elevation ofaivariable speed governor showingan example of springlever balancingmechanism in which; with only oneadjusting motion for a change of speedsetting, the balancing spring isdisplaced with. its centre-line parallel to itself and at 90 to thebalancing lever inf'its mid position thereby altering the transmissionratio of the lever and the deflection lxof'thezbalancing spring in sucha way that degree'of irregularity 'o-of the governor varies as .arequired function of the, speed-setting; the. example also providing-foradjustment of: said function;

Fig.1 2 'ishowsapa-rt" sectional elevation of adetail illustrating, an:'alternative guide-means for the balancing spring-0f Fig.1;

Fig. 3. shows apart sectional elevation of a complete variable speedgovernorembodyingan example of adjustable spring lever balancingmechanism. of the-:kind illustrated in Fig. 1, adapted to have .thesamedegree'of irregularity 6 at speed-settings of the lower part of therange, andvarying, 6 :in: the higher part of l the speedrange;

Fig: 4 shows; in part sectional elevation an alternative detail of thespring-lever balancing mechanism of Fig; l, with the angle between thecentre-line of the balancinggspringand the lever in its midposition'acute; andadjustable apart from changing ,the speed-setting;

Fig. 5 shows, in part sectional elevation"; a spring-lever. balancingmechanism similar to that shown in Fig. 1, with additional provisiorrforvarying the sleeve-travel 2Aa of the centrifugal mechanism during changeof speed-setting; which providesanyzrequired high order of stabil-v ity"with fewest dimensions adjustable;

Fig. 6 shows, in sectional elevation, a variable speed governorcomprising an embodiment of spring-lever balancing mechanism inwhich-,zw-ith only one-adjusting motion for a-change of speedsetting,-the transmissionwra-tioof A the :lever'is changed by adjustment oftheposition of its fulcrum, together with the deflection of thebalancing spring, which is arranged with its centre-line normal to theprimary'leverin its mid-position, being altered by a secondarylever insuch' a way that the degree of i-rregularity: remains constant for 'allspeed-settings.-

Fig. 7 shows, in sectional elevation, a-spring lever balancing mechanismof the'kind'illustrated in Fig. 6, but having amore general adjustmentmechanism (slotted slide) for the deflection :of the balancing spring,such that the degree ofirregularity varies on any required function ofthe speed-setting.

Fig. 8 shows, in partsectional elevation, an adjustable spring leverbalancing mechanism similar to that shown in Fig. 6, but having theangle s between the non-rotatable centre-line of the balancing springand the balancing lever in its mid-position an acute angle, themechanism being adapted to provide fi constant at all speedsettings Fig.9 shows, in part sectional elevation an alternative detail of theadjustment mechanism of Fig.z8-, with provision. for varying the degreeof irregularity .5 l as at requiredsfunction of the speedsetting, andmeans fonadjusting the initial-value Of 6-;

Fig. 10 shows, impart-sectional elevation; an adjustable spring leverbalancing mechanismsimilar to that shown in Fig; 7, with additionalprovision for. varying thesleeve-travel 2Aa of the centrifugal mechanismduring change of. speedsettin Fig. 11 shows, inpart sectional elevation;a governor embodying an' example of'springilever bal ancing mechanism,in which, fora =changet-of speed-setting;v the: point of action ofthesleeve of the centrifugal ..mechanism-.-on the balancing lever isdisplaced, together-with a-change of'defiection of the balancing spring,which remains at to the lever in 'itsmid-position all withponeadjustingmotion; such that the degreeof'lirregue larity is variedas--a-required-function ofthe spee d setting Fig. 12 shows; in partsectionaleelevation, a

spring-lever balancing mechanism in which for a change of speed-settingthe carrier for the balancing spring-means is rotated, thereby, with oneadjusting motion, the distance a: between the fulcrum of the primarylever and the point of action of the balancing spring thereon isadjusted, the angle between the centre-line of the balancingspring-means and the lever in its midposition is adjusted, and thedeflection IX of the balancing spring from its unstrained length U isadjusted, for varying the degree of irregularity of the governor as arequired function of the speed-setting.

Fig. 13 shows an alternative detail of Fig. 12, with a curved balancinglever;

Fig. 14. is a diagrammatic drawing required in connection with thegeneral description of the present invention.

The variable speed governor shown in Fig. 1 illustrates an embodiment ofspring-lever balancing mechanism in which, for a change ofspeed-setting, the distance 1. between the fulcrum B and the point ofengagement D of the sleeve with the lever remain unchanged, thetransmission ratio of the lever being changed by adjustment of thedistance BC=x between said fulcrum B and the point of engagement C ofthe balancing spring of the lever, proceeding with the angle onlybetween the centre-line of the spring and the lever in its mid-positionthe same at all speed-settings (spring displaced parallel to itself) andwith a corresponding change in the deflection lx of the balancing springsuch that the degree of irregularity 6 varies as a de sired function ofthe speed-setting, =f1(w The example of spring-lever balancing mechanismalso has provision for varying the function as which the degree ofirregularity 5 changes over the range of speed-settings.

In Fig. 1, a centrifugal mechanism of any suitable type, acting as speedresponsive device, is indicated diagrammatically at l2, mounted ongovernor-shaft and the governor casing E3, the governor shaft beingrotatable by means of flange it, which is adapted to be connected to theshaft of an engine to be governed. The sleeve-member Id of thecentrifugal mechanism is movable along shaft ll during governing aciton.

The spring-lever balancing mechanism comprises: the lever, with a yokepart i! and a straight arm is, fulcrummed on axle It in the governorcasing E3, the tension spring 2!, the anchorage 24 for the one end ofspring '2 l, which support immovable during governing action at the samespeed-setting, the connection means 22 between the other end of spring2! and part 19 of the lever, engaging said arm [9 by means of roller 23.and connection means between the yoke-part of the lever, 51, whichextends on both sides of sleeve it, said second connection means beingformed by two diametrically oppositely situated pins It on sleeve I5,engaging the forked ends of yoke arms ll of the lever. The means foreffecting adjustment of the transmissionratio of the lever together withan adjustment of the anchorage 2a of the spring 2! for a change ofspeed-setting are as follows:

The first connection means 22 between the end of thespring 2! and thelever-arm H is guided relative to a carriage I09 for anchorage 24, whichis immovable during governing at the same speedsetting, by a guide-meanscomprising fork t? fixed on carriage Hi8, and each respectively engagingone prong of said fork, two rollers :16

mounted on an arm 45, which is fixed to connection means 22, thecentre-line of the fork being arranged parallel to the centre-line ofthe spring, so that engagement piece 22 for the one end of the springcan move relative to the anchorage for the spring only along the line ofaction of the spring.

The anchorage it for the other end of the spring, which is slidablymounted on carriage lt-t between the secondary guide-surfaces Htextending parallel to the centre-line of the spring, engages, by meansof a pin it, a curved first guide-surface which is formed by the curvedslot 59 in the member Hi5, which is mounted in the governing casing. Thecarriage it"; for anchorage 25 is itself slidably mounted in thegovernor-casing it between a third straight set of guide-surfaces iii,extending normally to the centre-line of the spring means, and isfurther engaged by a screw H32 mounted in casing It, the said screwbeing rotatable from outside the casing by means of milled knob ortoothed wheel 5E3. This method of moving the carriage H38 is indicatedhere only by way of example, it being understood that any other methodof displacing carriage we and then keeping it in a desired position, isequally well applicable. The member iil i carrying the curved guide-slot89 for anchorage 26 is pin-jointed at end let to the governor casing it(or to a part fixed to casing l3) and has at its other end a forked endengaging a pin $88, which is fixed in a block SW. The block ml is fixedrelative to the casing during governing and ordinarily also during achange of speed-setting, being held between surfaces l2 by screw it?)mounted in the casing. If, however, it is required to adjust thedisposition of guide-slot es relative to casing l3, in order toinfluence the function, according to which the degree of irregularity isto vary over the range of speed-settings, as explained hereafter, theblock Hi? can be moved relative to the casing If; by rotation of screwI09 from outside the casing It, the head of screw I89 being accessibleoutside the casing to be rotated by means of a suitable key.

Similar provision, or other suitable provision, may also be made foraltering the position of end I06 of the member EM relative to thecasing, so that, member H31! can be displaced parallel to itself in thedirection of the line of action of the spring. This enables the governorto take spring of different unstrained lengths U, while the shape anddisposition of the curve described by the end A of the deflection of thespring, set off from point C, and corresponding to the curve of slot 9d,are unchanged, thus bringing about the same "irregularity-characteristicof the governor with spring of oif ferent unstrained lengths U0, orenabling adjustment to be made to lengthening of length U0 of a springafter prolonged use, to maintain the same characteristic.

Fig. 2 shows an alternative detail of a guidemeans arranged inside thespring, fork 3? being fixed on anchorage 2 3, and being engaged byrollers 96 on extension from the first connection'means 22. Its functioncorresponds to that of the guide-means described in Fig. 1.

The example of adjustable spring-lever balancing mechanism operates asfollows:

During governing at the same speed-setting, when the lever ll-l9 rocksabout fulcrum axle l8, corresponding to the motion of sleeve l5 of thecentrifugal mechanism, the connection means 21122.:of.:therbalancing'springi rzwithztheleverrarm l9movesalongtheacentreslinetoiz theispringspit being only capa'blei'ofizlsuch motion 1. due: tn the fork-roller guid'eemeans; anct' roller? 23-5at the first connection: meansz 221': has small: displac merits.backwardsand torwards aleng lever: arm [9.5 Due to= thexrollersAlt-Jimthef guide-means; which arez'ofrelatively-large diameter, as isalso roller 23, the mechanismshassfrem"thesewparts onlyrollingresistance against governing? motion, .whichi is extremel-y smalh,

The" arm 20= mounted 'on fulcrum-axle til'zoutsiderthe :casin'g: servesto transmit the governing: motion tea-thew 'control-organzrof :theengine to :be overned For a change of speed-setting; rotaticnof screw I02 by; meanssot knoblllaolutside thea casingmoves the carriage i alongits guide-surfaces l l l:, parallel tosthetleveri l9:inllitsi'midpositionz As both endsiof the spring (21 aretguided to be'capable of I motion relativeitoi' carriage 1 l 09? only along the line iof '7 action of 1 the springir due Lto anchorage 24' being. mountediintguides: H 0; and first: connection means 22. 1011" the r forkerollerguide-smeans, the. line 0-1? L actionaof i'sprin'g 21:- is moved?parallel .to itself; involvingdisplacement ofthe roller 23 along thelevert arm l9; andvthus the-"adjustment 0t distance: Simultaneously; the"anchorage 24 for the spri'ng isldisplaced along thei curved' slot 99;:termina the first guide sur face, theicompcnent fotf'this displacementot an:- chorage 24 1 wh-ich isiparallelto thev line ot -acti'en. of:spring 2!, changing the defiectionlxiof the spring.

The"= construction described with :reference :to Fig; 1: is anembodiment ot' the spning-1ever balancing mechanism of inventioninaccord ance with Equations (128-); (125-) and (129) 1 far theparticular case' -thattithe distance-EH 3! is constant andthatangleconstant and 90- so that; for any speed responsivedevice-ot knownproperties; the equations givethe shape of the guide=s1ot 99 withreferenceto the -right angles system ot co ordinates having its originat th'e fulcrum B of the lever; its X-axis along themid position oftheleverJ and its Ue' axisnormal thereto;

Consideration of the equations will show that for the special caseofet'-the same for" all speed settings,

is i constant, .for: which case then: the shape 0t guideeslot "98; i. e;the shape of the first guides surface for. the: spring-anchoragebecomes: a straight line, which encloses anr tanglevs 'z-BCet (asdistinct from angle "18 'BGAQ) I with the lever in 'its- -.mid-position,ands passes" through: a point Bqwhiehz is situated on' the. parallel tothe centrelinezCAWot the 'spring,.at a distance" from fulcrum B3 I Theconstruction" is further" adapted to talge springs of difierentunstrained length Uo"for the same-shape and disposition'ofslot 99; as'the member H14, carrying slotfiii; is made-displaceable parallel toitself; by providing a" further screw adjustment at the end "1 06 ofmember l'll li so that bot-h 'the ends I 01 and-"i 06 0f themem-ber canbe "displaced together parallel 'to' the centre line of -the springmeans. Displacement of only one end oi the membercause's ext-rotarychange at dispositien sesame, which will be seen' ll iomthe:firstastability-equations to cause a a difierent'developmentliofl'the degree of irregularity over between the lever'inits mid position' and-the centre-'line' ofeithe-spring means equal11090", and provision for effectingthat the degree of irregulaifiity ofthe'governor remains the same atall speed-settings,

centrifugal mechanism of a suitable type is indicated diagrammaticallyat l2, mounted on governor-shaft andeasing" I 3', shaft ll beingrotatable by means of flange I4.- The sleeveof the 'centrifugalmechanism is movable along shaft- I I with changes of shaft-speed. Thespl ingt-levier balancingmechanism comprises: an gled lever l'l-l9,fulcrumed on axlelil in 'the heusing.-= 3, the tension sprlng 2|, theanchorage u for'the' one'end-- of spring 2 l, which isimmovableduringegoverning. at the same speed-setting;

the;conneetiorrimeansil"between the other end of spring Zt and' arm IQof -th'e"lever,'engagingsaid arm through roller'23'; and azrsecondconnection means betweenth'eyoke-part ll of the lever-and sleeve l5;formed by diametrically oppositely situated =pins' I 6 on' -said sleeve;Anchoragez for spring 2lis mounted on guide surfaces 2'3 casing I 3,guide surfaces 28' being straight and at constant angle B to the midpos-ition of the -lever arm -l9, and is movable alongsaid guide-surfacefor changes of T speed-setting by screw 29, rotatable through wheelie,Con-trol lever 26' is mounted on axle I 8 outside casing is Ther m'eansfer guiding member 2 2* relative to sup ort: 2:4 is a -fork-rollermechanism as described for 1 like numerals denoting like parts, withfork lld-i'rectly fi'x 'ed to anchorage 24.

During governing as any speed' settingg the sp'tin'gqever balancingmechanism operates as follows When'the lever rocks; theconneotion means220i the-spring?! with the lever is can on'ly im'cve along the line ofaction of thespring, because :m'ember 15 withlits rollers- :is-constrained-to moveibetween the two prongs of tort;

' 4 parallel. to' the line of action of the spring,

and -xroliet zs therefore m'oves' along" the part 19 of the lever;

Ebr' a change ofi speed setting, rc'tation of screw' 25 by" kncbtilmoves the anchorage 2 3 a lohgthe-stfaight gui dc surfaces28 in thecasing, and, as the guide-means only permitsm'e tibn-of connection means22 relative to anchorage 1engthe-eentrelineef the spring, the rollerdisplaced-"along lever lS With' the'line of actien ot the spi'ingremaining parallel to its origin direction:- in all speed-settings,thustween the spring means and its otherwise immovable anchorage 2%along a straight line guidesurface B A, for which point 3 is situated ona line through the fulcrum B, and parallel to the centre-line of thespring, at a distance BB=U0, the unstrained length of the spring meansfrom fulcrum B, and which guide-surface B A encloses a constant angle 5with the lever-part 19 in its mid-position, effects that the degree ofirregularity d. is constant over the whole range of speed-settings. Themagnitude of 6a; which is kept constant over the range ofspeed-settings, is seen from the equations to depend on the magnitude ofangle ,8, of the arm DB=y (measured normally to the direction of motionof sleeve id of the centrifugal mechanism), and on the sleevetravelZna'.

For the speed-settings, for which the point of engagement C is on thecurved part 59 of the lever, 6 varies according to a required functionof w the required curvature of the lever-part 59 having been determinedin accordance with the equations.

Fig. shows a detail illustrating a modification of the spring leverbalancing mechanism shown in Fig. 1, like numerals denoting like parts,the diiference being that here provision is shown to adjust thecentre-line CA of the spring means to any required angle to the lever inits midposition, which angle is to be kept constant for allspeed-settings. Here the carriage [til for the spring-anchorage 25,instead of being of one piece, as in Fig. 1, comprises a separate part 13 for carrying the spring-means with the guidemeans therefor, includingthe anchorage 2% for the spring, which is slidably mounted between thesecondary guide-surfaces I it, and the fork-roller guide-means for theengagement piece 22. The part H3 is mounted on the base 596 of thecarriage by some suitable means, here indicated by way of example as alocked nut, such that the centre-line of the spring means can be set atany desired angle-4 to the lever-arm E9 in its midposition. Themechanism operates exactly as that described with reference to Fig. l,the possible adjustment of angle 5 being another method of adjusting thefunction, according to which 5 varies over the range of speed-settings.

The detail of Fig. applied to the mechanism of Fig. 1 makes this anembodiment of a springlever mechanism in accordance with the Equations(54), (144) and (155). Consideration of the equations shows that initialadjustment of angle changes the initial value of 6 which is varied as arequired function of the speed-setting with a suitably curved guide-slot99, and which is kept constant over the speed-range with a straightguide-slot 99. I

Fig. 5 shows, in sectional elevation, an example of an embodiment of aspring lever balancing mechanism in which the speed-setting is changedby displacement of the balancing spring parallel to itself, with specialattachment for varying the sleeve-travel or" the centrifugal mechanismtogether with the speed-setting to suit a required development of thedegree of irregularity Bxmo) over the range of speed-settings and, moreparticularly, to provide a construction of any required higher order ofstability than the springlever mechanism it is applied with, as statedin the general description. This special attachment may be applied withany of the constructions described in this specification.

The spring-lever balancing mechanism here shown is substantially thesame as that already described" with reference to Fig. 1, like numeralsdenoting like parts; it only differs from that of Fig. 1 in the shape ofthe guide-slot 99 for the anchorage 24 of the balancing spring-means,and in the method of engagement between the sleeve [5 of the centrifugalmechanism and the balancing lever, which is by means of a frame i2!extending from said sleeve and carrying a roller 639 for engaging saidlever.

The governor further has, instead of the lever 20 fixed on the fulcrumaxle i8, as in Fig. 1, a different mechanism for engaging thecontrolorgan (or servo-motor) of the engine to be governed, whichmechanism also embodies the provision for varying the sleeve travel withchange of speed-settings, as follows:

The balancing lever has an extension 642 beyond the point of engagementD therewith of the roller 639 from the sleeve, and this extension isengaged by two rollers are of a member 6 3! This member is guided bymeans of two further rollers 643 in the guide-surfaces 6% of a carrier6%, so that this member 64! is only capable of motion in the directionnormal to the lever in its midposition. Further, this member engages bymeans of a, fork 6 extending parallel to the balancing lever in its saidposition, a pin 546 at the end of a rod t ll, which leads out of thegovernorcasing to the control-organ (or servo-motor) of the engine to begoverned, member 64 !fi representing the third connection means,engaging both the lever and the control-rod leading to the control-organof the engine to be governed. The screws 849 and 650 set in the carrier640 11-1 it the motion of the member 641 in the direction normal to thelever in its mid-position, thereby also limiting themotion in thatdirection of the point on the balancing lever, which is engaged by therollers E 58, and thus the travel of the sleeve of the centrifugalmechanism.

The carriage 640 is mounted on a guide-surface 652, which extendsparallel to the lever in its mid-position, and is movable for a changeof speed-setting, by a displacement means shown diagrammatically at 653,actuated by a continuation 65! of the screw I02, which also moves thespring-carriage I of the spring-lever balancing mechanism. Displacementof the carrier 649 is seen to change the position, at which rollers 64%engage the lever, and hence, with the distance between the stops 6 39and 656 constant, the magnitude of the sleeve-travel. Depending on therequirements, the displacement may be such as to eifect a displacementof the carrier in the same direction as that'of the spring-carrier lililwith the same actuating motion of knob IE3, or in the oppositedirection.

It will be understood that the screws are merely shown as diagrammaticrepresenations of the means for moving both the carriers Hi0 and 648 inany desired way respectively for a change of speed-setting, and forkeeping these carriers fixed in theirrespective positions for governingat the same speed-setting, and that any suitable provision for bringingabout this effect may be applied.

The provision shown operates as follows:

. For a change of speed-setting, say an increase in speed-setting, thescrew I 02 moves the carrier H351 to the right, and carrier 640 to theleft. This displacement of carrier M30, as has already been explainedwith reference to Fig. 1, increases the speed-setting together withdecreasing the degree of irregularity, due to the shape of theguide-slot 99, even with the same sleeve-travel,

